A large number of physical books exist whose owners have purchased them, and by means of that purchase, royalties due authors have been paid. Many of these books are stored and no longer used by their owners, are donated, or discarded. Still others are sold as used to others with no royalty due the author under the legal principle of copyright exhaustion. Under this principle, the digital rendition of a specific physical book that can no longer be used may be legally eligible for loan or resale to another user since the content, not the physical existence of a print book, is the substance of the copyright.
Some e-books are produced simultaneously with the production of a printed format, as described in electronic publishing, though in many instances they may not be put on sale until later. Often, e-books are produced from pre-existing hard-copy books, generally by document scanning, sometimes with the use of robotic book scanners, having the technology to quickly scan books without damaging the original print edition. Scanning a book produces a set of image files, which may additionally be converted into text format by an Optical Character Recognition (OCR) program. Occasionally, as in some e-text projects, a book may be produced by re-entering the text from a keyboard.
Digital Rights Management (DRM) mechanisms may be employed to prevent such digital renditions from being shared or copied among end-users. A secondary market which allows users to effectively and legally transfer “used” digital objects to others while maintaining scarcity is beyond scope of this invention and is addressed by pending and allowed patents. A “used” digital object is one which at inception was digital in form in such context.
As use of digital objects increases, users may wish to transfer the digital objects to other users. These transfers may include a sale, a rental, a gift, a loan, a trade, a sale of digital rendition rights etc. However, several problems manifest when transferring a digital object. While a physical object such as a copy of a paperback book only exists in one place at a time, easy and inexpensive copies of a digital object without loss of fidelity are possible. Thus, easy copying and repeated sale of the same digital object is possible, potentially eliminating scarcity of the digital object. Because of this, many owners implement digital rights management to prevent such impermissible transfers. Furthermore, the digital object as originally transferred to the initial purchaser may have license restrictions or other limitations on permissible use or further transfer. For example, a license to use a free download of a popular song may expire after a few days.
A secondary market which allows users to effectively and permissibly transfer “used” digital objects, or digital renditions of used print objects, to others while maintaining scarcity is therefore desired. A “used” digital object is one to which a user has legitimately obtained access or ownership rights (hereinafter “access rights”), and to which the user may permissibly transfer to another user.